What is the remainder when 6^39 is divided by 7?
Answer and explanation
Correct answer: D. 6
- Step 1: Find the repeating cycle of powers of 6 modulo 7. Step 2. Reducing the exponent 39 by the cycle length gives remainder 6. Answer: 6. Why not the others: 0 is what you get if you use a wrong cycle length. 1 is what you get if you use a wrong cycle length. 5 is what you get if you use a wrong cycle length.
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